4.1.4 SERIAL_STATE Notification
The MCP2222 notifies parity or framing errors through Interrupt Endpoint 0x01 (IN). The format is given in the following table.
| Byte Index | Notification | Description | |
|---|---|---|---|
| 0 | 0xA1 | vmRequestType | Device to host |
| 1 | 0x20 | bRequest | Request code |
| 2 | 0x00 | wValue – lower byte | Reserved |
| 3 | 0x00 | wValue – higher byte | |
| 4 | 0x00 | wIndex – lower byte | Interface 0 |
| 5 | 0x00 | wIndex – higher byte | |
| 6 | 0x02 | wLength – lower byte | Payload length in bytes |
| 7 | 0x00 | wLength – higher byte | |
| 8 |
|
Framing error Parity error |
wState (Error State) Bit 0-3: Unused. Bit 4: Represents a framing Error: 0 – no framing error, 1 – framing error. Bit 5: Represents a parity error: 0 – no parity error, 1 – parity error. Bit 6-15: Unused. |
| 9 | 0x00 | wState - higher byte | |